Packard Forum Index » Post-War (1946-54)

Thanks everyone!!

Have you made the change?
If so, how is it working for you and do you have a comparison to share?

Hi I been using B&M Trick Shift in my 51 300 and so far no issues so I will continue to use it.

No idea if Trick Shift would fully fit the description of synthetic but when a former poster suggested using it some years ago, his description said overall it was very similar to type F which was the recommended replacement for the original and no longer available at the time type A the factory specified for use in Ultramatics.

Trick Shift was recommended because of its different additives from type F. At the time, Dexron was made for a smooth almost imperceptible shift in GM transmissions with their synthetic friction material. With the original cork clutch facings in an Ultramatic, it sometimes caused the cork clutches to slip too much when engaging and that allowed overheating as the clutches kept spinning as they tried to grab. Type F was extra grabby which the cork facings like unless they have gotten hard and glazed. The additives in Trick Shift do a commendable job of providing a decent grab while also doing a slight softening of the cork. That softening helps to quieten a noticeable and sometimes annoying noise that often happened when a direct drive clutch with a glazed cork facing had difficulty grabbing when going into direct drive. Reducing the noise was the original reason for the Trick Shift recommendation.

Unknown is if a partially rebuilt transmission which would only have some of the GM type linings would see benefits from Trick Shift. Most seem to do OK with ordinary F or in the case of full rebuilds, modern Dexron type fluids.

I will get with you when I make the change, right now everything is on hold. I am having back surgery and have to put my car on standby right now. I will let you know when I get out of the procedure. I have been told a solid 6-weeks!